Based on social exchange theory, we developed and tested a mediated moderation model to investigate the effects of psychological contract breach (PCB), person-organization fit (P-O fit) and high-performance work system (HPWS) on employee engagement. Using a sample of 255 employees in China, our results revealed that PCB has significant negative effect on employee engagement, and P-O fit partially mediates this relationship. We further found that high levels of perceived HPWS aggravate not buffer the negative effect of PCB on employee engagement and P-O fit. In addition, the interaction of HPWS and PCB on employee engagement is mediated by P-O fit. Implications for the research and practices, limitations and directions for future research are discussed.